Conventional TV screens reproduce a video signal by means of a sweeping electron beam. Essentially, the electron beam will sweep back and forth horizontally along a series of rows. The intensity of the electron beam itself is modulated by the video portion of the TV signal, applied to the electron gun grid so that for each sweep of the beam along a row, the emitted light from the screen resulting from the electron impingement upon phosphor making up the screen is modulated in accord with this video signal. The resulting picture is generated for viewing.
It is found that the light emitted by the phosphors of the screen can be damaging to human eyes over prolonged periods. Further, the electron beam must travel over a given length to accommodate deflection and focusing coils and the like. As a result, the television screen is relatively bulky; that is, it requires space to accommodate the depth of the structure.